The synthetic elastic fiber known as spandex, a name which comes from an anagram of “expands,” is used in a wide range of clothing and apparel from sportswear to casual clothing to undergarments. Spandex also has applications in medical dressings such as diapers and bandages. One recent market research study forecast a 10.3 percent compound annual growth rate (CAGR) between 2015 and 2021, when the global spandex market was expected to reach $8.7 billion in value. By 2023, global sales of spandex are likely to exceed 1,550 kilotons thanks in part to growing demand for active sportswear with garment stretch as well as increasing applications, such as automotive door panel fabrics.
The development of spandex, or Lycra, fiber was not originally pursued for the material’s use in any medical dressing or sportswear, however. This 20th century invention came about in an attempt to improve the comfort of women’s undergarments by replacing rubber with a material providing suitable elasticity. The development of spandex also features the story of a persistent inventor who was able to use his chemistry expertise to solve a problem which others at his company had given up on.
This Tuesday, February 27th, marks the 56th anniversary of the issue of the original patent covering spandex fibers. The inventor of spandex, Joseph C. Shivers, Jr., is a 2018 inductee into the National Inventors Hall of Fame. As the anniversary date of this important advancement in synthetic fibers approaches, we’re revisiting our Evolution of Technology series to see how this renowned inventor was able to create a new industry in fiber materials and a product which has become ubiquitous throughout various clothing products.
Joseph Shivers Keeps Trying to Create a Rubber Alternative After DuPont Shelves the Project
Born on November 29th, 1920, in Marlton, NJ, Shivers would complete his studies from the undergraduate level through his doctoral degree at Duke University, earning a Ph.D. in organic chemistry in 1946. While he was still a graduate student at Duke, Shivers worked with the U.S. government to develop antimalarial drugs for use by soldiers serving overseas in World War II.
Soon after graduating, Shivers was hired by DuPont to work as a research chemist focusing on the area of polymers. Through the latter half of the 1940s, Shivers worked as part of a DuPont research team which was formed in order to find a synthetic elastomer material capable of replacing rubber in undergarments. Not only was rubber uncomfortable to wear so close to the body but the U.S. government had control over the supply of rubber during WWII, leaving many companies in search of a synthetic solution which could be readily manufactured.
The DuPont research team wasn’t successful at finding a synthetic alternative to rubber. The team did find a material that was both form-fitting and could expand, but an inability to contract caused the material to form unattractive bulges. The research team was disbanded in 1950 but Shivers kept at the development of elastomers which could be used as a rubber substitute. Working with the polyester material Dacron, Shivers modified that material with another substance to create an elastic fiber which could be spun into filaments and withstand high temperatures.
Spandex Becomes a Global Phenomenon
What Shivers had created was spandex and his improvements are detailed in U.S. Patent No. 3023192, titled Segmented Copolyetherester Elastomers and issued on February 27th, 1962, listing Shivers as the lone inventor. It claimed a segmented copolymer having an elastic recovery of at least 90 percent and a stress decay below about 25 percent consisting of a multiplicity of recurring intralinear etherester and ester units; the etherester units composed about 35 percent to about 75 percent of the weight of the segmented copolymer, with the ester units composing the rest of the material’s weight. As the ‘192 patent noted, the elastic polymer yarns of this invention had higher strength and higher stress modulus, or the force required to elongate yarn by a given percentage, than any rubber threads. Other advantages of the yarn when compared to rubber threads included the ability to be spun into multifilament yarns, a very low inherent color and a good resistance to perspiration and greases, making them ideal for being worn against the skin.
By the end of the 1950s, Shivers had accomplished the task which had previously stymied DuPont researchers. The material, which would be marketed by the company as Lycra, retained its elasticity even when being stretched to five times its original length and still recover close to its original dimensions when released. However, WWII had drawn to a close many years before and the rubber shortage it caused had ended as well. Further, spandex was being commercialized around the same time that pantyhose became a fashionable women’s undergarment, reducing the demand for the girdles which DuPont had hoped to make more comfortable.
It’s a testament to the usefulness of spandex that it has found such a wide degree of commercial uses since it was introduced six decades ago. In 1968, the French Olympic ski team reportedly used clothing made with Lycra fibers in competition and the incorporation of spandex into sportswear increased through the 1970s. Brightly colored spandex clothing became a fashion statement in the 1980s and could be easily spotted outside of the typical confines of workout videos. Over time, global production of spandex increased in Germany, Japan and South Korea to meet global demand. In 2010, 80 percent of the 20.5 billion garments purchased by Americans that year included spandex as a material. By this time, DuPont had exited its position in its Lycra brand, having sold that part of its fiber business to Koch Industries in 2004 for $4.4 billion. Last November, Chinese textile firm Shandong Ruyi Group agreed to purchase the Lycra business from Koch for more than $2 billion.
The legacy of Shivers as the inventor of spandex has previously led to professional recognition such as the 1998 Olney Medal for Achievement in Textile Chemistry. He was also a recipient of DuPont’s Lavoisier Medal, an award given by the company to scientists and engineers who make significant contributions to DuPont’s business. His induction to the National Inventors Hall of Fame comes posthumously, but modern society continues to reap the benefits of Shivers’ inability to let go of a problem many years ago.